146 MAN AND THE GLACIAL PERIOD. 



Cardigan Bay at some distance from the coast in conflu- 

 ence with the ice from mid- Wales ; and, as I have sug- 

 gested, may have passed over St. David's Head. 



" Returning now towards the head of the glacier we may 

 follow with advantage its left bank downward. The ice- 

 flow on the Cumberland coast appears to have resembled 

 very much that in North Wales. A great press of ice 

 from the northward (Galloway) seems to have had a pow- 

 erful 'easting' imparted to it by the conjoint influences 

 of the thrust of the Irish ice and the inflow of ice from 

 the Clyde. Whatever may have been the cause, the effect 

 is clear : about Ravenglass cleavage took place, and a flow 

 to northward and to southward, each bending easterly. 

 By far the larger mass took a southerly course and bent 

 round Black Combe, over Walney, and a strip of the main- 

 land about Barrow in Furness, and out into and across 

 Morecambe Bay. Its limits are marked in the field by 

 the occurrence of the same rocks which characterise it in 

 Anglesea, viz., the granites of Galloway and of west and 

 central Cumbria. 



" The continued thrust shouldered in the glacier upon 

 the mainland of Lancashire, but the precise point of 

 emergence has not yet been traced, though it cannot be 

 more than a few miles from the position indicated on the 

 map. I should here remark, that all along the bounda- 

 ries the Irish Sea Glacier was confluent with local ice, 

 except, probably, in that part of the Pennine chain to the 

 southward of Skipton. Down to Skipton there was a 

 great mass of Pennine ice which was compelled to take 

 an almost due southerly course, and thus to run directly 

 athwart the direction of the main hills and valleys. A 

 sharp easterly inflection of the Irish Sea Glacier carried it 

 up the valley of the Ribble, and thence, under the shoul- 

 der of Pendle, to Burnley, where Scottish granites are 

 found in the boulder- clay. 



" On the summit of the Pennine water-shed, at Heald 



